My objective is to determine the nature of the anomalous retinal projections associated with oculocutaneous hypopigmentation. Subjects will be mice of a single inbred strain (C57BL/6J) which are litter-mates that differ in pigmentation but are otherwise genetically identical (coisogenic). In each mouse one optic nerve will be cut and allowed to degenerate. Then each brain will be sectioned and strained, and the distribution of degenerating axon terminals in the lateral geniculate nucleus will be mapped from photomicrographs. To determine the nature of the "albino anomaly" I will compare oculo-cutaneously pigmented (black) vs. unpigmented (albino) mice. Post-operative time allowed for degeneration of the severed optic nerve axons will vary; this will permit assessments of the projections of different types of axons with differing rates of degeneration. These studies are relevant to work on human syndromes (e.g., strabismus), neurological mutants, recovery of function, and comparative neuroanatomy.